Keratinolytic activity from new recombinant fusant AYA2000, derived from endophytic<i>Micromonospora</i>strains
Bibliographic record
Abstract
Two different endophytic strains, ESRAA1997 and ALAA2000, were isolated from the Egyptian herbal plant Anastatica hierochuntica. The 2 strains produced alkaline serine protease and were identified based on their phenotypic and chemotypic characteristics as different strains of Micromonospora spp. Both strains grew and produced keratinase, using different keratinous waste substances as the sole source of carbon and nitrogen. In our study, the activity and properties of keratinase enzymes of the wild strains ESRAA1997 and ALAA2000 were altered by genetic recombination through protoplast fusion between them, leading to a potent keratinolytic fusant Micromonospora strain AYA2000 with improved properties (activity, stability, specificity, and tolerance to inhibitors). Using a mixture of yeast extract, peptone, and malt extract as a supplement to the bovine hair medium increased keratinase production by 48%, and addition of 1% glucose suppressed enzyme production by Micromonospora strain AYA2000. The enzyme was purified by ammonium sulphate precipitation and DEAE-cellulose chromatography followed by gel filtration. The molecular weight, estimated using SDS-PAGE, was 39 kDa. The enzyme exhibited remarkable activity towards all keratinous wastes used and could also adapt to a broad range of pH and temperatures, with optima at pH 11 and 60 °C. The enzyme was not influenced by chelating reagents, metal ions, or alcohols. These properties make AYA2000 keratinase an ideal candidate for biotechnological application.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".